1. Field of the Invention
This invention relates generally to filtration systems, and more particularly to a combination relief valve and filtration system that enables gasses to vent from a hydrocarbon distribution system while limiting pollution released into the atmosphere.
2. Description of Related Art
A known problem in the art of hydrocarbon distribution (hereby defined to include any form of transportation and storage or hydrocarbons) is that gasses can build up to unacceptably high levels within the hydrocarbon distribution system, and these gasses must be vented to relieve pressure within the system.
Various valves are commonly used in the art to release the gasses once pressure reaches a certain level. A vent valve (e.g., an ENARDO® valve) is commonly used for this purpose, although those skilled in the art may devise many alternative valves that are also acceptable.
A well known problem with venting the gasses is the pollution caused by venting the hydrocarbons, and associated chemicals (e.g., benzene, etc.). The standard solution to the problem of pollution has been to burn the vented gasses. The new and improved systems involve complex systems for capturing, compressing, and utilizing the gas. These types of systems are not practical for small scale releases of gas, such as this invention addresses, such as capturing vented gas from Enardo valves.
Wynn, U.S. Pat. No. 7,350,581, teaches a vapor recovery apparatus for oil and gas well production that is used in combination with a liquid separator, a sales line, a holding tank, and a compressor linked to an engine. A first conduit extends from fluid communication with the holding tank to a compressor inlet, while a second conduit extends from a compressor outlet to fluid communication with the sales line. The vapor recovery apparatus also has an electronic controller that is connected to the engine and to a pressure sensor, which is in fluid communication with the gas in the tank. When the pressure reaches a certain level, the gas is captured and compressed by the compressor, and directed to the holding tank for future use.
Webb, U.S. Pat. No. 5,195,587, teaches in an oilfield production system in which a water driven jet pump is used to evacuate vapors from storage tanks to thereby recover the vapors and prevent emissions from passing to the atmosphere. The jet pump entrains the vapors in process water which is passed to a process separator already in the system. The gas is separated for recovery.
Heath et al., U.S. 2007/0186770, teaches a natural gas well vapor recovery processing system and method that is adapted for recovering gaseous hydrocarbons to prevent their release into the atmosphere. The natural gas is collected and compressed using a compressor for later collection and use.
Mok et al., U.S. 2010/0095845, teaches a vent gas adsorption system and a method of recovering volatile organic compounds (VOCs), more particularly to a vent gas adsorption system devised to effectively adsorb VOCs included in the vent gas and reduce VOC content of the vent gas, and a method of recovering VOCs.
Various forms of filters are, of course, well known. Meyers, U.S. Pat. No. 6,684,945, for example, teaches an air filter for a well is installed within a well casing of the well. The air filter forming an airtight seal around the well casing of the well, such that all the air that enters and exits the well must pass through the air filter. The air filter preferably includes a filter housing, at least one removable gasket and a removable filter cartridge installed within an opening extending through the filter housing. The air filter prevents dirt, dust, bacteria, gaseous chemicals, volatile organic compounds, (VOCs), insects and other air born contaminants from entering and possibly contaminating the well. An air filter may also be installed within a vent pipe extending through a well seal attached to the top of a well casing of a well.
The prior art teaches venting gasses from a hydrocarbon distribution system, and burning such vented gasses. The prior art also teaches collecting the gasses, and compressing them for use. However, the prior art does not teach a combination relief valve and filtration system that enables gasses to vent from the hydrocarbon distribution system through a filter for limiting pollution released into the atmosphere. The present invention fulfills these needs and provides further related advantages as described in the following summary.